Sar Processing for Profile Reconstruction and Characterization of Dielectric Objects on the Human Body Surface (original) (raw)
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Specific absorption rate (SAR) inside spherical human head model for half-wave radiating dipole antenna has been investigated at the frequency range from 500 MHz to 3 GHz using finite difference in time domain (FDTD) method. The effects of variation of reflection coefficient and resonant frequency of the antenna due to presence of head model are also presented in this paper. The human head is modeled as inhomogeneous sphere of 19 cm diameter consists of a uniform core representing human brain, surrounded by two spherical shells representing skull and skin. Distance between the head and antenna is varied from 1 cm to 3 cm to calculate the maximum local SAR induced inside the head. At some frequencies the maximum local SAR becomes more than the FCC and IEEE's upper safety limit for the distance between the head and antenna less than 1 cm and 0.6 Watt radiated power.